1. Field of the Invention
The present invention generally relates to a recording-medium holder insertion detection apparatus, and more particularly to a recording-medium holder insertion detection apparatus which detects an insertion of a cassette holder into a housing of a magnetic recording/reproducing system, such as a digital audio tape (DAT) recorder system.
In recent years, there have been the demands for inexpensive, lightweight magnetic recording/reproducing systems, and there is the increasing demand for a cassette holder insertion detection apparatus having an inexpensive, lightweight structure that is appropriate for use in the magnetic recording/reproducing systems.
2. Description of the Related Art
FIG. 4 shows a conventional recording-medium-holder insertion detection apparatus. The conventional insertion detection apparatus is provided for use in a digital audio tape (DAT) recording/reproducing system.
As shown in FIG. 4, a cassette holder 104 includes a DAT cassette 110 provided therein. The cassette holder 104 is inserted into the recording/reproducing system so as to reproduce information recorded in the DAT of the cassette 110. The conventional insertion detection apparatus is configured such that the cassette holder 104, when inserted, is movable between an insert/eject position and a tape-loaded position in a housing 102 of the recording/reproducing system. With the cassette holder 104 being set at the tape-loaded position, the recording/reproducing system can reproduce information recorded in the DAT of the cassette 110.
In the conventional insertion detection apparatus of FIG. 4, the cassette holder 104 is provided with a projection 112, which is formed on the bottom of the cassette holder 104 so as to downwardly extend from the bottom of the cassette holder 104. In the housing 102 of the recording/reproducing system, a position-sensing switch 106 is provided at a given position, and the position-sensing switch 106 includes a knob 114, which upwardly extends from the top of the position-sensing switch 114.
When the cassette holder 104 at the insert/eject position is manually pushed by an operator in the insertion direction indicated by the arrow xe2x80x9cX1xe2x80x9d in FIG. 4, to reach the given position where the position-sensing switch 106 is provided, the projection 112 on the bottom of the cassette holder 104 is brought into contact with the knob 114 on the top of the position-sensing switch 106. The position-sensing switch 106 is turned ON by the contact of the projection 112 with the knob 114, which outputs a detection signal, which indicates that the manual insertion of the cassette holder 104 into the housing 102 is detected, to a system control unit 108.
When the detection signal output by the switch 106 is received at the system control unit 108, the system control unit 108 supplies a drive signal to a motor driver (not shown). In response to the drive signal supplied by the system control unit 108, the motor driver supplies a drive voltage to a loading motor (not shown) so that the loading motor is rotated by the drive voltage. The rotating force of the loading motor is transmitted to the cassette holder 104 through gears, so that the cassette holder 104 is further moved in the insertion direction to the tape-loaded position. With the cassette holder 104 being set at the tape-loaded position, the recording/reproducing system can reproduce information recorded in the DAT of the cassette 110.
In the conventional insertion detection apparatus described above, the manual insertion of the cassette holder 104 into the housing 102 is detected by using the position-sensing switch 106 when the projection 112 on the bottom of the cassette holder 104 is brought into contact with the knob 114 on the top of the position-sensing switch 106.
However, in the above conventional insertion detection apparatus, the misalignment of the projection 112 on the cassette holder 104 and/or the misalignment of the knob 114 on the position-sensing switch 106 are likely to occur, which will result in a poor contact between the projection 112 and the knob 114. In such a case, even when the cassette holder 104 at the insert/eject position is manually inserted to reach the given position where the position-sensing switch 106 is provided, the position-sensing switch 106 is not turned ON due to the poor contact, and no detection signal is supplied from the position-sensing switch 106 to the system control unit 108. As the system control unit 108 supplies no drive signal to the motor driver, the motor driver does not supply a drive voltage to the loading motor in order to generate a rotating force of the loading motor. Hence, the cassette holder 104 is not moved in the insertion direction to the tape-loaded position, and the recording/reproducing system cannot reproduce information recorded in the DAT of the cassette 110.
In order to eliminate the above problem, in the conventional insertion detection apparatus, the alignment of the projection 112 on the cassette holder 104 and the alignment of the knob 114 on the switch 106 must be carried out with high accuracy. This will cause the manufacture of the conventional insertion detection apparatus to become costly and complicated. Hence, it is difficult for the conventional insertion detection apparatus to detect the manual insertion of the cassette holder in the recording/reproducing system by using a lightweight, low-cost structure. The conventional insertion detection apparatus employs the position-sensing switch 106, and it requires the highly accurate alignment of the projection 112 and the knob 114 in order to provide a safe, reliable detection of the insertion of the cassette holder 104 in the recording/reproducing system.
In order to overcome the above-described problems, preferred embodiments of the present invention provide a recording-medium holder insertion detection apparatus that provides a safe, reliable detection of the insertion of the cassette holder in the recording/reproducing system by using a lightweight, inexpensive structure.
According to one preferred embodiment of the present invention, an apparatus for detecting an insertion of a recording-medium holder in a recording/reproducing system, includes: a motor which is engaged with the recording-medium holder, placed at a first position within the recording/reproducing system, the motor moving the holder in an insertion direction from the first position when the motor is rotated by a drive voltage, and the motor generating an alternating voltage when the motor is rotated by a manual insertion of the holder so as to reach a second position; a detection circuit which outputs a pulsed signal in response to the alternating voltage generated by the motor; and a determination unit which calculates a distance of the holder away from the first position in the insertion direction based on the pulsed signal output by the detection circuit, and outputs a drive-start signal when the calculated distance has reached a predetermined distance between the first position and the second position.
The recording-medium holder insertion detection apparatus of the present invention is effective in providing a safe, reliable detection of the insertion of the cassette holder in the recording/reproducing system by using a lightweight, inexpensive structure.